Blower construction

ABSTRACT

A centrifugal or cross-flow blower has its rotor and/or stator formed from one or more resinous elements of annular crosssection, such as rings or sleeves, with a multiplicity of generally radial channels, each element being a unitary cellular strip bent into cylindrical shape. Several rings with different channel orientations may be concentrically nested.

United States Patent [191 Hubert et a1.

1451 Apr. 16, 1974 BLOWER CONSTRUCTION Buderussche Eisenwerke AG,Wetzlar, Germany Filed: Oct. 12, 1971 Appl. No.: 188,362

Assignee:

Foreign Application Priority Data Oct. 14, 1970 Germany 2050324 Mar.12,1971 Germany 2111914 US. Cl 415/54, 415/211, 415/206, 416/181,416/231, 55/471 Int. '01....F04d'17/00, F04d 29/26, F04d 17/10 Field ofSearch 415/211, 54, 121 G, 231, 415/90; 416/186, 181; 261/91, 92;277/53,

References Cited UNITED STATES PATENTS 7/1909 Harder 415/90 2,655,31010/1953 Schlumbohn 416/231 795,938 8/1905 Seymour, Jr 416/181 2,658,70011/1953 Howell 1 415/54 3,018,896 l/l962 Gewiss 416/131 3,046,648 7/1962Kelly 277/53 3,123,286 3/1964 Abbott 416/231 3,128,940 4/1964 McDonald416/231 3,276,415 10/1966 Laing 415/54 FOREIGN PATENTS OR APPLICATIONS383,594 11/1932 Great Britain... ..416/l8l 884,822 5/1943 France 415/211Primary Examiner-I-lenry F. Raduazo Attorney, Agent, or Firm-Karl F.Ross; Herbert Dubno ABSTRACT 8 Claims, 9 Drawing Figures I I t u I n l IPATENTEDAPR 16 874 SHEET 1 BF 2 BLOWER CONSTRUCTION Our presentinvention relates to a blower, of the centrifugal or cross-flow type,with a rotor comprising an annular array of generally radially orientedvanes.

In conventional, rotor construction, in which these vanes have the formof blades on a solid ring or between a pair of such rings, the number ofvanes and therefore of fluid passages is limited by the need foravoiding excessive flow resistance. These relatively large passages areconducive to columnal oscillation of the air or other fluid passingthrough so, that the opera tion of such blowers generates considerablenoise.

An important object of our invention is to provide an improved vanestructure for a blower, especially for the rotor thereof, which canefficiently circulate air or other fluids in a quiet and substantiallyvibration-free manner.

Another object is to provide a rotor construction of light weight andcentrally symmetrical configuration, requiring little or no balancing,which can be easily and inexpensively manufactured from startingmaterials currently available.

These objects are realized, pursuant to our invention, by utilizing aunitary element of annular cross-section with generally radial channels,the solid parts of this element constituting the vanes of the rotor or,if desired, those of an associated stator.

A radially channeled ring or sleeve of this description may consist,basically, of a honeycomb strip of limitedly flexible polymericmaterial, e.g. polyvinylchloride, cast integrally and bent into acylinder whose edges are joined by thermal fusion or adhesive bonding.The strip may also be sliced from a larger block, provided that itschannels or cells are sufficiently resistant to crushing or have beentemporarily rigidified by a filler such as ice as is well known per se.Instead of being integrally molded, such a block or strip can also becomposed of a bank of tubes, e.g. of polyethylene, fused or cemented toone another. The term honeycomb, as used herein, does not necessarilyimply a hexagonal cell profile but designates more generally amultiplicity of parallel channels arrayed in several relativelystaggered rows.

The channels, and therefore the intervening web portions constitutingthe blower vanes, need not be precisely radial but may be slightly skewto the shaft axis, as where a swirling motion of the generated flow isdesired; in some instances, e.g. for greater structural rigidity, therotor (or the stator) may comprise nested rings whose channels aremutually aligned but extend at different angles to the radial direction.

The above and other features of our invention will be described ingreater detail hereinafter with reference to the accompanying drawing inwhich:

FIG. 1 is a side-elevational view of a centrifugal blower embodying ourinvention;

FIG. 2 is a cross-sectional view taken on the line II--II of FIG. 1;

FIG. 3 is a view similar to FIG. 2, showing a modification;

FIG. 4 is a fragmentary axial view of a rotor and a stator in a bloweraccording to our invention;

FIG. 5 shows part of a channeled strip from which the rotor of thepreceding Figures may be formed;

FIG. 6 is an axial sectional view of a cross-flow blower according tothe invention; and

FIGS. 7-9 are longitudinal sectional views of differ ent types of rotorfor the blower of FIG. 6.

The centrifugal blower of FIG. 1 comprises a housing 1 in which a shaft11 driven by a motor (not shown) supports a rotor 2 more fullyillustrated in FIG. 2. This rotor comprises a cage 3 with an opening atone end for the entry of an air stream, the closed opposite end beingintegral with a hub 13 keyed onto the shaft 11. Cage 3, advantageouslyconsisting of plastic material, has bars 3a supporting a ring 4 ofsimilar material formed with a multiplicity of elongate radial channels14 separated by webs 16. These webs may be considered as vanes directingthe air radially outward as the ring rotates at high speed about itsaxis.

FIG. 3 shows a somewhat modified structure in which the cage 3 has beenreplaced by a disk 5 having a hub 15, the ring 4 being cemented to thisdisk.

FIG. 4 shows a stator 6 juxtaposed with the rotor 2, this statorconsisting of a pair of nested rings 7 and 8 similar to and coaxial withthe ring 4 of the rotor. The cage bars 3a are received in the annularclearance between the channeled bodies 4 and 6. The majority of thechannels 17 of ring 7 are aligned with respective channels 18 of ring 8,the latter being skew to the axis of rotation 0 whereas the former areradial like the channels 14 of rotor ring 4. It will be apparent thatthe rotor 2 could also include a plurality of nested rings withdifferent angular orientation of their respective channels.

The channeled body of rotor ring 4 or of stator ring 7, 8 may be derivedfrom a honeycomb strip as partly shown in FIG. 5, the channels of thestrip being defined by an array of juxtaposed resinous tubes bonded toone another. The inner diameter of these tubes should, of course, belarge enough to prevent clogging by solids entrained by the circulatingair stream.

In FIG. 6 we have shown a cross-flow blower 1' whose housing forms adisk 20 about a rotor 12 having the same basic structure as the rotor 2of the centrifugal blower 1 shown in FIG. 1. Disk 20 narrows in thedirection of rotation, whereby air or some other working fluid enteringat an inlet port 21 is forced into the rotor body in the zone ofconvergence and is centrifugally discharged therefrom at an outlet port22.

In FIG. 7 the body 4 of rotor 12 is a cylindrical sleeve cantilevered atone end on a supporting disk 9 which is mounted on drive shaft 11, theother end of this sleeve being bonded to a disk 9' having a centralaperture for the introduction of a counterbearing. FIG. 8 shows therotor body as axially split into several rings 4, similar to the ringsof FIGS. 14, which are separated by disks 9" provided with peripheralflanges 19; the disks are spaced apart by tubes 10 mounted on thethroughgoing shaft 11. According to FIG. 9, the rings 4 are separated byflat disks 9 similar to those of FIG. 7, only the first disk beingbonded to shaft 11.

Naturally, the specific rotor and stator shapes given by way ofillustration may be modified in accordance with particular requirements.

In FIG. 6, a line xx marks the meeting edges of a channeled strip whichhave been. bonded together to form the cylindrical body 4. With thechannels of this body all skew to the rotor axis, the strip may havebeen formed by slicing a larger block along a plane intersecting thechannels at an angle deviating somewhat from As clearly seen in FIGS. 2,3 and 7-9, the channels 14 of the cylindrically tubular element 4 arearrayed in a plurality of axially spaced peripheral rows. With ahoneycomb pattern, such as that shown in FIG. 5, the channels ofadjacent rows are relatively staggered.

We claim:

1. In a blower having an annular array of generally radially orientedvanes, the improvement wherein said vanes are constituted by the solidparts of at least one unitary resinous element of cylindrically tubularconfiguration provided with a multiplicity of generally radial elongatechannels arrayed in a multiplicity of axially juxtaposed peripheralrows, said element comprising a plurality of coaxially nested ringsrigidly interconnected with their respective channels substantiallyaligned but oriented at different angles to the radial direction.

2. The improvement defined in claim 1 wherein said element is a flexiblestrip bent into a cylinder.

3. The improvement defined in claim 2 wherein said strip has a honeycombpattern of channels, the channels of adjacent rows being relativelystaggered.

4. The improvement defined in claim 1 wherein said element forms part ofa rotor, further comprising a rotary support for said element mounted ona shaft.

5. The improvement defined in claim 4 wherein said support is anopen-ended cylindrical cage surrounding said element.

6. The improvement defined in claim 4 wherein said support is a diskbonded to said element.

7. The improvement defined in claim 4 wherein said support comprises aplurality of axially spaced disks, said element being split into severalcoaxial rings separated by said disks.

8. The improvement defined in claim 4 wherein said element is spacedlysurrounded by a stationary guide ring also provided with a multiplicityof generally radial

1. In a blower having an annular array of generally radially orientedvanes, the improvement wherein said vanes are constituted by the solidparts of at least one unitary resinous element of cylindrically tubularconfiguration provided with a multiplicity of generally radial elongatechannels arrayed in a multiplicity of axially juxtaposed peripheralrows, said element comprising a plurality of coaxially nested ringsrigidly interconnected with their respective channels substantiallyaligned but oriented at different angles to the radial direction.
 2. Theimprovement defined in claim 1 wherein said element is a flexible stripbent into a cylinder.
 3. The improvement defined in claim 2 wherein saidstrip has a honeycomb pattern of channels, the channels of adjacent rowsbeing relatively staggered.
 4. The improvement defined in claim 1wherein said element forms part of a rotor, further comprising a rotarysupport for said element mounted on a shaft.
 5. The improvement definedin claim 4 wherein said support is an open-ended cylindrical cagesurrounding said element.
 6. The improvement defined in claim 4 whereinsaid support is a disk bonded to said element.
 7. The improvementdefined in claim 4 wherein said support comprises a plurality of axiallyspaced disks, said element being split into several coaxial ringsseparated by said disks.
 8. The improvement defined in claim 4 whereinsaid element is spacedly surrounded by a stationary guide ring alsoprovided with a multiplicity of generally radial channels.